USE OF RUNS TEST TO ASSESS CARDIOVASCULAR AUTONOMIC FUNCTION IN DIABETIC SUBJECTS

OBJECTIVE - We suggest a simple, noninvasive method to assess the auto nomic function in diabetic subjects. The method requires only a monito ring of heart rate (HR) with subjects in the sitting position. RESEARC H DESIGN AND METHODS - Sixty diabetic subjects, 44 men and 16 women, b etween 20-80 years of age, were recruited, chronologically, for this s tudy. Subjects treated for high blood pressure were not included. Thei r autonomic function was assessed by the total score of five classical cardiovascular function tests. In the same subjects and in 44 healthy subjects, blood pressure and HR were determined from beat to beat by the Finapres system with subjects in the sitting position. We examined the randomness of the HR changes by calculating the z statistic of th e runs test on 1,000 successive HR readings (the z value is low if the HR changes are random). When the HR changes are random, we consider t hat the autonomic control of HR is impaired. RESULTS - The z values of HR changes were significantly lower in diabetic subjects compared wit h normal subjects (2.98 +/- 0.97 vs. 3.54 +/- 0.97, P < 0.004). In dia betic subjects, the z value was closely correlated to the total score of disautonomy (r = - 0. 66, P < 0.0001, after correction for age effe ct) and to the office systolic blood pressure (r = -0.43, P < 0.001). CONCLUSIONS - The z value of HR changes might be a marker of the auton omic function in diabetic subjects.